logP is an importat paramter for evaluating the hydrophobicity of organic compounds and other species. It is widely used in 2D-QSAR and recently in 3D-QSAR studies. On the basis of the current fragment addition method...logP is an importat paramter for evaluating the hydrophobicity of organic compounds and other species. It is widely used in 2D-QSAR and recently in 3D-QSAR studies. On the basis of the current fragment addition method, we proposed a new algo rithm called XLOGP by introducing atomic paramters like atom accessible surfaces, van der Waals volums and partial charges. Step-wise multiple regression on a test set of 400 orgtanic compounds were carried out. The model was then tested by cross-validation. The final correlation coefficient for the whole data set fitting and for cross -validation is 0.982 and 0.971, respectively. This shows that the model obtained is valid both at data fitting and at prediction. Compared to other algorithm, this method can discriminate a common atom or fragment in different environment.展开更多
A new lnethod is presented for the calculation of octanol/water partition coefficients.On the basis of summation of atomic contributions, our algorithm, namely;XLOGP, also incorporate correction factors into the calcu...A new lnethod is presented for the calculation of octanol/water partition coefficients.On the basis of summation of atomic contributions, our algorithm, namely;XLOGP, also incorporate correction factors into the calculation. Multivarlate regression aIlalysis was performed on a traming database of 1831 organic compounds with diverse structures to give the final model. The correlation coefficients for the whole set fitting is 0.968 and the standard deviation is O.37. The result sllows that our model is accturate enough for logP estmimation in QSAR studies. Compared to other similar approashes, our method gives better results and is more convenient to use.展开更多
文摘logP is an importat paramter for evaluating the hydrophobicity of organic compounds and other species. It is widely used in 2D-QSAR and recently in 3D-QSAR studies. On the basis of the current fragment addition method, we proposed a new algo rithm called XLOGP by introducing atomic paramters like atom accessible surfaces, van der Waals volums and partial charges. Step-wise multiple regression on a test set of 400 orgtanic compounds were carried out. The model was then tested by cross-validation. The final correlation coefficient for the whole data set fitting and for cross -validation is 0.982 and 0.971, respectively. This shows that the model obtained is valid both at data fitting and at prediction. Compared to other algorithm, this method can discriminate a common atom or fragment in different environment.
文摘A new lnethod is presented for the calculation of octanol/water partition coefficients.On the basis of summation of atomic contributions, our algorithm, namely;XLOGP, also incorporate correction factors into the calculation. Multivarlate regression aIlalysis was performed on a traming database of 1831 organic compounds with diverse structures to give the final model. The correlation coefficients for the whole set fitting is 0.968 and the standard deviation is O.37. The result sllows that our model is accturate enough for logP estmimation in QSAR studies. Compared to other similar approashes, our method gives better results and is more convenient to use.